I, too, had this problem when I had a problem with the latest beta. I had installed from my CDs and then done the upgrades via Stardock Central. When I tried to uninstall from Control Panel -> Add/Remove Programs, it just told me it couldn't because the uninstall file had been removed. I had to do what Bichur said and uninstall GC by running Stardock Central, going to Games, selecting GC and uninstalling from there.
